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Basic Information on restor


Task: restor
Purpose: Restore clean components to make the CLEAN map
Categories: deconvolution

RESTOR is a MIRIAD task which performs a number of functions
typically performed after the deconvolution step. These include
generating a "CLEAN" map, calculating residuals and convolving
a model by a gaussian beam.

RESTOR can also handle multi-frequency synthesis data. In this
case the input dirty map should consist of just one plane. The input
beam may contain several planes, and the input model may have no
more planes (but possibly fewer) than the beam. To get the residuals,
each plane in the model is convolved with the corresponding plane in
the beam, and subtracted from the dirty map.

Key: model
The model of the deconvolved cube. Usually this will be produced
by CLEAN or MAXEN. The units of this image should be Jy/pixel. No
default.

Key: beam
The input dirty beam. No default.

Key: map
The input dirty cube, which should have units of Jy/beam. This
can be omitted when mode=convolve. Otherwise no default.

Key: mode
This can be one of the values:
  "clean"     This is the normal use, and the default, where the
              output is the map, less the model convolved by the
              dirty beam, plus the model convolved by the gaussian
  "residual"  The output is the map, less the model convolved by the
              dirty beam.
  "convolve"  The output is the model convolved by the gaussian. The
              map parameter is ignored, and the beam is needed only if
              the user does not give the gaussian fwhm and pa.
  "dirty"     The output is the map convolved with the beam.

Key: fwhm
The size, in arcsec, of the gaussian beam to use in the
restoration. This will normally be two numbers, giving the
full-width at half-maximum of the major and minor axes of the
gaussian. If only one number is given, the gaussian will have
equal major and minor axes. If no values are given, they are
either retrieved from the beam header, or computed by fitting a
gaussian to the given dirty beam.

Note that the model image is convolved with this gaussian beam, and
then added to the residuals. These residuals are not affected by the
choice of this gaussian beam size. So if you want the residuals and
convolved image to have approximately the same beam size, then
the gaussian beam size chosen should be the same size as the dirty beam.
If you want coarser resolution than that provided by this, you
should use task CONVOL to smooth the restored image afterwards.

Key: pa
The position angle, in degrees, of the gaussian restoring beam,
measured east from north. The default is determined from the dirty
beam fit (The value for PA is ignored, if no value is given for
FWHM).

Key: out
The output restored image. No default.

User Guide References to restor

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Generated by smamiriad@cfa.harvard.edu on 09 Jul 2012